AI 中文总结
本研究通过约230 MeV/核子的核子敲出反应，结合DWIA等理论计算，测得$^{52-54}$Ca的1p中子轨道比0f$_{7/2}$中子轨道大0.48-0.78 fm，价质子轨道大小演化因统计不确定性较大尚无定论。
AI 中文摘要
本研究通过约230 MeV/核子的核子敲出反应，探究了$^{52}$Ca、$^{53}$Ca、$^{54}$Ca和$^{55}$Sc的中子与质子单粒子轨道的大小。确定方法基于对$(p,pn)$和$(p,2p)$反应中碎片动量分布的测量，该方法对被敲出核子波函数的空间延展度敏感，在扭曲波玻恩近似（DWIA）框架下进行解读。本研究对$(p,pn)$反冲动量分布方法开展了系统性敏感性研究。将实验测得的动量分布，与结合DWIA反应理论计算的最先进平均场、从头算介质相似重整化群及自洽格林函数计算结果进行对比。基于本研究，在$^{52-54}$Ca中，1p中子轨道始终被发现比0f$_{7/2}$中子轨道大0.48-0.78 fm；而由于相关统计不确定性较大，价质子轨道的大小演化仍无定论。
英文摘要
The size of neutron and proton single-particle orbitals of $^{52}$Ca, $^{53}$Ca, $^{54}$Ca, and $^{55}$Sc were investigated via nucleon knockout reactions at $\sim$ 230 MeV/nucleon. The determination method is based on the measured fragment momentum distributions in $(p,pn)$ and $(p,2p)$ reactions, which are shown to be sensitive to the spatial extension of the wave function of the knocked-out nucleon, interpreted within the distorted wave impulse approximation (DWIA) framework. A systematic sensitivity study is carried out for the $(p,pn)$ recoil-momentum distribution method and is presented in this work. The experimental momentum distributions are compared to state-of-the-art mean field and $ab$ $initio$ in-medium similarity renormalization group and self-consistent Green's function calculations in combination with DWIA reaction theory calculations. Based on this work, the 1$p$ neutron orbitals are consistently found $0.48-0.78$ fm larger than the $0f_{7/2}$ neutron orbitals in $^{52-54}$Ca, while the size evolution of the valence proton orbitals remains inconclusive due to the large associated statistical uncertainties.
Comments17 pages, 18 figures
